Lung cancer is the most common cause of death from cancer in the United States. Previous studies of screening with chest radiographs and sputum cytology have not been shown to decrease lung cancer mortality. For the first time, a randomized screening trial with low-dose computed tomography scans has demonstrated a 20% lung cancer mortality reduction compared with screenings with a chest x-ray. Investigation is underway on many breath, sputum, and blood biomarkers to determine markers of high risk. The hope is that some (or one) of them will add to the early detection of lung cancer observed with low-dose computed tomography.